ABC's Mike beoettcher, thank you. Meantime, up and down the east coast, millions are cleaning up in the aftermath of hurricane Arthur, which brought heavy rains and flooding to new England. This car sitting on a flooded highway in New Bedford, Massachusetts. And in nags head, north Carolina, near where Arthur first made landfall late Thursday, this man trying to cross a highway that's been turned into a river. Arthur is now a post-tropical storm and moving off the coast, and we're tracking its latest movements, but first, ABC's Alex Perez on the new threat to beach-goers this holiday weekend. Reporter: Tonight, the cleanup is just beginning. In New Bedford, Massachusetts, Arthur inundating entire neighborhoods with water, dumping up to eight inches of rain. Most of it in just six hours. Many here salvaging what they can after the storm left basements under water. Water was right up to here. Reporter: Flooded streets stranding drivers. Look at it, past the curb. Water is unbelievable here. Reporter: Arthur, now a post-tropical cyclone, today whipped through Maine and Canada. In North Carolina, the storm spawned a tornado with 100-mile-an-hour winds that tore through homes. This man raced with his kids to seek shelter in their bathroom. The ceiling was collapsing behind us. Reporter: Arthur tossing these travel trailers and boats like toys. With crowds now packing beaches, the storm creating another big concern -- dangerous rip tides. A Maryland surfer and three life guards trying to help, all had to be rescued after they got caught in the current Friday. Rip currents can form when strong waves break at the shore as the water moves back to sea, taking swimmers with it. Experts say, in a rip current, it's best to swim parallel to the shore. And experts say, remember, you should never try to swim against a rip current. It could tire you out and possibly make matters worse. The key, again, they say, is to swim parallel to the shore and, of course, remain calm and try not to panic. Rebecca? Good advice. Alex Perez, thank you.

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